Machine tools such as lathes, milling machines or drill heads that are used in manufacturing to mechanically remove material from a work-piece normally operated at a relatively low speed and high output power. In some cases, a work-piece being machined by such machine tools may require additional machining by other types of tool that are suitable for example for performing more accurate machining using small diameter tools. This additional machining may require additional setup and machining time.
Spindles provide for increased production, and improved overall efficiency of machining devices. However, known spindles may be very complex and often constructed from very expensive components such as advanced bearing assembly and motors. Hence, spindles tend to be very expensive, which limit their usage to only very high production quantities and high cutting qualities. An alternative solution is spindle speeders (also referred to as spindle speed increasers or multipliers). These devices may be assembled on the machining devices and rotate together with the main spindle of the machine devices. Thus, the overall rotation speed of the assembly may be the algebraic sum of the rotation speed of the spindle speeders and the rotation speed of the main spindle of the machining device.
Turbine driven rotor machine tools that operate at relative higher speeds may be suitable for performing for example the above mentioned accurate machining. These tools typically have a spindle that is supported for rotation by accurate and often expensive bearings and a replaceable machining bit that is detachable secured to the spindle. U.S. Pat. No. 7,192,248 and International Patent Publication WO 2011/001421 A1 describe a turbine driven rotary cutting tool that has support for attaching the turbine cutting tool to a conventional machine tool holder. The turbine cutting tool has a spindle which is supported by bearings and the spindle is provided with a tool holder that is adapted to grip a cutting bit.